﻿<!DOCTYPE html>
<html>
<head>
  <title>Tool for Reshaping a Sector of a Circle</title>
  <!-- Copyright 1998-2020 by Northwoods Software Corporation. -->
  <meta name="description" content="A demonstration of the SectorReshapingTool extension." />
  <meta name="viewport" content="width=device-width, initial-scale=1">

  <script src="../release/go.js"></script>
  <script src="../assets/js/goSamples.js"></script>  <!-- this is only for the GoJS Samples framework -->
  <script src="SectorReshapingTool.js"></script>
  <script id="code">
    function init() {
      if (window.goSamples) goSamples();  // init for these samples -- you don't need to call this

      var $ = go.GraphObject.make;

      myDiagram =
        $(go.Diagram, "myDiagramDiv",
          {
            "animationManager.isEnabled": false,
            "undoManager.isEnabled": true
          });

      // install the SectorReshapingTool as a mouse-down tool
      myDiagram.toolManager.mouseDownTools.add(new SectorReshapingTool());

      function makeSector(data) {  // Geometry converter for the node's "LAMP" Shape
        var radius = SectorReshapingTool.getRadius(data);
        var angle = SectorReshapingTool.getAngle(data);
        var sweep = SectorReshapingTool.getSweep(data);
        var start = new go.Point(radius, 0).rotate(angle);
        // this is much more efficient than calling go.GraphObject.make:
        var geo = new go.Geometry()
          .add(new go.PathFigure(radius + start.x, radius + start.y)  // start point
            .add(new go.PathSegment(go.PathSegment.Arc,
              angle, sweep,  // angles
              radius, radius,  // center
              radius, radius))  // radius
            .add(new go.PathSegment(go.PathSegment.Line, radius, radius).close()))
          .add(new go.PathFigure(0, 0))  // make sure the Geometry always includes the whole circle
          .add(new go.PathFigure(2 * radius, 2 * radius));  // even if only a small sector is "lit"
        return geo;
      }

      myDiagram.nodeTemplate =
        $(go.Node, "Spot",
          {
            locationSpot: go.Spot.Center, locationObjectName: "LAMP",
            selectionObjectName: "LAMP", selectionAdorned: false
          },
          new go.Binding("location", "loc", go.Point.parse).makeTwoWay(go.Point.stringify),
          // selecting a Node brings it forward in the z-order
          new go.Binding("layerName", "isSelected", function(s) { return s ? "Foreground" : ""; }).ofObject(),
          $(go.Panel, "Spot",
            { name: "LAMP" },
            $(go.Shape,  // arc
              { fill: "yellow", stroke: "lightgray", strokeWidth: 0.5 },
              new go.Binding("geometry", "", makeSector)),
            $(go.Shape, "Circle",
              { name: "SHAPE", width: 6, height: 6 })
          ),
          $(go.TextBlock,
            {
              alignment: new go.Spot(0.5, 0.5, 0, 3), alignmentFocus: go.Spot.Top,
              stroke: "blue", background: "rgba(255,255,255,0.3)"
            },
            new go.Binding("alignment", "spot", go.Spot.parse).makeTwoWay(go.Spot.stringify),
            new go.Binding("text", "name"))
        );

      myDiagram.model = new go.GraphLinksModel([
        { name: "Alpha", radius: 70, sweep: 120 },
        { name: "Beta", radius: 70, sweep: 80, angle: 200 }
      ]);

      myDiagram.commandHandler.selectAll();  // to show the tool handles
    }
  </script>
</head>
<body onload="init()">
<div id="sample">
  <div id="myDiagramDiv" style="border: solid 1px black; width:100%; height:600px"></div>
  <p>
    Two of the handles permit changing the angles of the sector; one handle permits changing the radius of the sector.
  </p>
  <p>
    Note that the <a>Geometry</a> returned by <code>makeSector</code> always returns a Geometry that
    occupies the area that would be occupied by a full circle.  That Geometry-creating function also
    depends on three data properties, <code>radius</code>, <code>angle</code>, and <code>sweep</code>.
  </p>
</div>
</body>
</html>